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The effects of ionizing radiation on materials often reduce to "bad news." Radiation damage usually leads to detrimental effects such as embrittlement, accelerated creep, phase instability, and radiation-altered corrosion. This last point merits special attention. Elucidating synergies between radiation and corrosion has been one of the most challenging tasks impeding the deployment of advanced reactors, stemming from the combined effects of high temperature, corrosive coolants, and intense particle fluxes. Here we report that proton irradiation significantly and repeatably decelerates intergranular corrosion of Ni-Cr alloys in molten fluoride salt at 650C. We demonstrate this effect by showing that the depth of intergranular voids resulting from Cr leaching into the salt is reduced by the proton irradiation alone. Interstitial defects generated from proton irradiation result in radiation-enhanced diffusion, more rapidly replenishing corrosion-injected vacancies with alloy constituents, thus playing the crucial role in decelerating corrosion. Our results show that in industrially-relevant scenarios irradiation can have a positive impact, challenging our view that radiation damage always results in negative effects., Comment: 4 figures plus one supplementary figure, 11 pages in total

Aside from the historical Molten Salt Reactor Experiment, a few in-reactor loops, and one electron irradiation/corrosion facility, dedicated facilities to test the combined effects of molten salt corrosion and irradiation on materials do not currently exist. A major gap therefore exists in rapid, reactor-relevant materials testing capabilities which, if remedied, would greatly hasten molten salt reactor development. We present a new accelerator-based facility for rapid, simultaneous testing of molten salt-facing materials utilizing a proton beam as the radiation source. Introducing proton irradiation to a molten salt corrosion system poses specific engineering concerns in sample and corrosion cell design, operational stability, integration with the accelerator beamline, and radiation safety. This paper describes how these requirements were fulfilled with confirmatory tests and results.

In liquid–fueled molten salt reactor designs, materials will be exposed to a molten salt containing a multitude of fission products and other corrosive species. Little work has been done to understand the unique corrosion characteristics of materials in fission product-laden liquid–fuel systems. In this study, we conducted corrosion experiments up to 150 h in duration which exposed four commercial alloys (Hastelloy N, Incoloy 800H, 316L stainless steel, and Ni–201) to three molten salt compositions in order to better understand corrosion in liquid–fuel systems and inform reactor design. It was found that the presence of simulant fission product species, at predicted concentrations, in a highly corrosive FLiNaK + EuF3 molten salt does not lead to any detectable increase in corrosion at reactor–relevant conditions. No penetration of simulant fission product species into the samples was detected. The unique corrosion morphology of each of the alloys tested in this work is discussed. In particular, Ni–201 was found to be an ideal salt–facing material in molten fluoride systems, and is essentially immune to corrosion.

Li2TiO3 is one of the most promising candidates among tritium breeders. In this work, Li2TiO3 pebbles with a narrow size distribution, high density, small grain size, and good sphericity are synthesized using the commercial Li2TiO3 powder as the raw material by a co-flow capillary-based microfluidic wet process. Highly uniform slurry droplets containing Li2TiO3 powder and polyvinyl alcohol were formed in the microfluidic device and then solidified with the cross-linking reaction between polyvinyl alcohol and borax. Li2TiO3 pebbles were finally obtained after sintering the green bodies. The size of sintered Li2TiO3 pebbles with a good sphericity (Dmax/Dmin < 1.05) can be controlled precisely in a size range of 400–1000 µm by adjusting the flow rate of disperse and continuous phases. The effects of the calcination method, sintering condition, solid content of slurry, and the particle size of Li2TiO3 powder on the relative density of Li2TiO3 pebbles prepared were studied in detail, and 97.16% T.D. (Theoretic...

This paper analyses the development of Internet of Things (IoT) and introduces essential techniques of IoT. In order to solve problems in smart substation construction, this paper analyses the situation of substation construction in Anhui, and proposes an integrated management system of IoT in the Jinxiu substation in the smart grid construction area of Binhu district of Hefei in Anhui. This integrated management system of IoT demonstrates the effective application of IoT technology in building smart substation.

The size-controlled Pt/C/PTFE hydrophobic catalyst pellets employed in the hydrogen–water isotope exchange reaction were prepared using microfluidic technology. An assembly–disassembly capillary-based microfluidic system was demonstrated for easy fabrication of narrow size-distribution catalyst beads (CV ＜ 5%), and the size of the beads were precisely controlled in the range of 150–1500 μm by manipulating the flow rate of the disperse and continuous phase, as well as the continuous phase viscosity. Approximately 3 nm platinum nanoparticles with uniform dispersion in a porous PTFE/C support were synthesized by γ-ray-induced reduction without using any chemical reducing agents. Polyvinyl alcohol (PVA) was introduced as both a solidified agent and porogen in the fabrication process. The porosity of the as-prepared catalyst pellets were characterized using a scanning electron microscope (SEM) and a BET instrument, and the hydrophobicity of the catalyst was examined by observation of the contact angle between water and the surface of the catalyst beads.